Effect of Inorganic Salts on the Isobaric Vapor−Liquid Equilibrium of the Ethyl Acetate−Ethanol System

The effect of various salts such as magnesium nitrate, calcium nitrate, zinc nitrate, and magnesium chloride on vapor−liquid equilibrium (VLE) of the ethyl acetate−ethanol system was studied experimentally in a modified Othmer still at atmospheric pressure. The influence of cation and anion of the salts on the VLE of the ethyl acetate− ethanol system was examined. It was observed that the order of effect of salts for breaking the azeotrope was Zn(NO3)2 > Ca(NO3)2 > Mg(NO3)2 > MgCl2. Salting-out coefficients were calculated using the scaled particle theory. The experimental vapor−liquid equilibrium data with salt was compared with that calculated using the scaled particle theory, and the agreement was satisfactory. Thus, it may be seen that the scaled particle theory can be used to estimate the salt effect of polar solvents in nonaqueous systems.